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24 
25 #include "precompiled.hpp"
26 #include "classfile/systemDictionary.hpp"
27 #include "code/codeCache.hpp"
28 #include "code/compiledIC.hpp"
29 #include "code/icBuffer.hpp"
30 #include "code/nmethod.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "interpreter/interpreter.hpp"
33 #include "interpreter/linkResolver.hpp"
34 #include "memory/metadataFactory.hpp"
35 #include "memory/oopFactory.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "oops/method.inline.hpp"
38 #include "oops/oop.inline.hpp"
39 #include "oops/symbol.hpp"
40 #include "runtime/handles.inline.hpp"
41 #include "runtime/icache.hpp"
42 #include "runtime/sharedRuntime.hpp"
43 #include "runtime/stubRoutines.hpp"
44 #include "utilities/events.hpp"
45 
46 
47 // Every time a compiled IC is changed or its type is being accessed,
48 // either the CompiledIC_lock must be set or we must be at a safe point.
49 
50 //-----------------------------------------------------------------------------
51 // Low-level access to an inline cache. Private, since they might not be
52 // MT-safe to use.
53 
cached_value() const54 void* CompiledIC::cached_value() const {
55   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
56   assert (!is_optimized(), "an optimized virtual call does not have a cached metadata");
57 
58   if (!is_in_transition_state()) {
59     void* data = get_data();
60     // If we let the metadata value here be initialized to zero...
61     assert(data != NULL || Universe::non_oop_word() == NULL,
62            "no raw nulls in CompiledIC metadatas, because of patching races");
63     return (data == (void*)Universe::non_oop_word()) ? NULL : data;
64   } else {
65     return InlineCacheBuffer::cached_value_for((CompiledIC *)this);
66   }
67 }
68 
69 
internal_set_ic_destination(address entry_point,bool is_icstub,void * cache,bool is_icholder)70 void CompiledIC::internal_set_ic_destination(address entry_point, bool is_icstub, void* cache, bool is_icholder) {
71   assert(entry_point != NULL, "must set legal entry point");
72   assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
73   assert (!is_optimized() || cache == NULL, "an optimized virtual call does not have a cached metadata");
74   assert (cache == NULL || cache != (Metadata*)badOopVal, "invalid metadata");
75 
76   assert(!is_icholder || is_icholder_entry(entry_point), "must be");
77 
78   // Don't use ic_destination for this test since that forwards
79   // through ICBuffer instead of returning the actual current state of
80   // the CompiledIC.
81   if (is_icholder_entry(_call->destination())) {
82     // When patching for the ICStub case the cached value isn't
83     // overwritten until the ICStub copied into the CompiledIC during
84     // the next safepoint.  Make sure that the CompiledICHolder* is
85     // marked for release at this point since it won't be identifiable
86     // once the entry point is overwritten.
87     InlineCacheBuffer::queue_for_release((CompiledICHolder*)get_data());
88   }
89 
90   if (TraceCompiledIC) {
91     tty->print("  ");
92     print_compiled_ic();
93     tty->print(" changing destination to " INTPTR_FORMAT, p2i(entry_point));
94     if (!is_optimized()) {
95       tty->print(" changing cached %s to " INTPTR_FORMAT, is_icholder ? "icholder" : "metadata", p2i((address)cache));
96     }
97     if (is_icstub) {
98       tty->print(" (icstub)");
99     }
100     tty->cr();
101   }
102 
103   {
104     MutexLockerEx pl(SafepointSynchronize::is_at_safepoint() ? NULL : Patching_lock, Mutex::_no_safepoint_check_flag);
105 #ifdef ASSERT
106     CodeBlob* cb = CodeCache::find_blob_unsafe(_call->instruction_address());
107     assert(cb != NULL && cb->is_compiled(), "must be compiled");
108 #endif
109     _call->set_destination_mt_safe(entry_point);
110   }
111 
112   if (is_optimized() || is_icstub) {
113     // Optimized call sites don't have a cache value and ICStub call
114     // sites only change the entry point.  Changing the value in that
115     // case could lead to MT safety issues.
116     assert(cache == NULL, "must be null");
117     return;
118   }
119 
120   if (cache == NULL)  cache = (void*)Universe::non_oop_word();
121 
122   set_data((intptr_t)cache);
123 }
124 
125 
set_ic_destination(ICStub * stub)126 void CompiledIC::set_ic_destination(ICStub* stub) {
127   internal_set_ic_destination(stub->code_begin(), true, NULL, false);
128 }
129 
130 
131 
ic_destination() const132 address CompiledIC::ic_destination() const {
133  assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
134  if (!is_in_transition_state()) {
135    return _call->destination();
136  } else {
137    return InlineCacheBuffer::ic_destination_for((CompiledIC *)this);
138  }
139 }
140 
141 
is_in_transition_state() const142 bool CompiledIC::is_in_transition_state() const {
143   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
144   return InlineCacheBuffer::contains(_call->destination());;
145 }
146 
147 
is_icholder_call() const148 bool CompiledIC::is_icholder_call() const {
149   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
150   return !_is_optimized && is_icholder_entry(ic_destination());
151 }
152 
153 // Returns native address of 'call' instruction in inline-cache. Used by
154 // the InlineCacheBuffer when it needs to find the stub.
stub_address() const155 address CompiledIC::stub_address() const {
156   assert(is_in_transition_state(), "should only be called when we are in a transition state");
157   return _call->destination();
158 }
159 
160 // Clears the IC stub if the compiled IC is in transition state
clear_ic_stub()161 void CompiledIC::clear_ic_stub() {
162   if (is_in_transition_state()) {
163     ICStub* stub = ICStub_from_destination_address(stub_address());
164     stub->clear();
165   }
166 }
167 
168 //-----------------------------------------------------------------------------
169 // High-level access to an inline cache. Guaranteed to be MT-safe.
170 
initialize_from_iter(RelocIterator * iter)171 void CompiledIC::initialize_from_iter(RelocIterator* iter) {
172   assert(iter->addr() == _call->instruction_address(), "must find ic_call");
173 
174   if (iter->type() == relocInfo::virtual_call_type) {
175     virtual_call_Relocation* r = iter->virtual_call_reloc();
176     _is_optimized = false;
177     _value = _call->get_load_instruction(r);
178   } else {
179     assert(iter->type() == relocInfo::opt_virtual_call_type, "must be a virtual call");
180     _is_optimized = true;
181     _value = NULL;
182   }
183 }
184 
CompiledIC(CompiledMethod * cm,NativeCall * call)185 CompiledIC::CompiledIC(CompiledMethod* cm, NativeCall* call)
186   : _method(cm)
187 {
188   _call = _method->call_wrapper_at((address) call);
189   address ic_call = _call->instruction_address();
190 
191   assert(ic_call != NULL, "ic_call address must be set");
192   assert(cm != NULL, "must pass compiled method");
193   assert(cm->contains(ic_call), "must be in compiled method");
194 
195   // Search for the ic_call at the given address.
196   RelocIterator iter(cm, ic_call, ic_call+1);
197   bool ret = iter.next();
198   assert(ret == true, "relocInfo must exist at this address");
199   assert(iter.addr() == ic_call, "must find ic_call");
200 
201   initialize_from_iter(&iter);
202 }
203 
CompiledIC(RelocIterator * iter)204 CompiledIC::CompiledIC(RelocIterator* iter)
205   : _method(iter->code())
206 {
207   _call = _method->call_wrapper_at(iter->addr());
208   address ic_call = _call->instruction_address();
209 
210   CompiledMethod* nm = iter->code();
211   assert(ic_call != NULL, "ic_call address must be set");
212   assert(nm != NULL, "must pass compiled method");
213   assert(nm->contains(ic_call), "must be in compiled method");
214 
215   initialize_from_iter(iter);
216 }
217 
set_to_megamorphic(CallInfo * call_info,Bytecodes::Code bytecode,TRAPS)218 bool CompiledIC::set_to_megamorphic(CallInfo* call_info, Bytecodes::Code bytecode, TRAPS) {
219   assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
220   assert(!is_optimized(), "cannot set an optimized virtual call to megamorphic");
221   assert(is_call_to_compiled() || is_call_to_interpreted(), "going directly to megamorphic?");
222 
223   address entry;
224   if (call_info->call_kind() == CallInfo::itable_call) {
225     assert(bytecode == Bytecodes::_invokeinterface, "");
226     int itable_index = call_info->itable_index();
227     entry = VtableStubs::find_itable_stub(itable_index);
228     if (entry == NULL) {
229       return false;
230     }
231 #ifdef ASSERT
232     int index = call_info->resolved_method()->itable_index();
233     assert(index == itable_index, "CallInfo pre-computes this");
234     InstanceKlass* k = call_info->resolved_method()->method_holder();
235     assert(k->verify_itable_index(itable_index), "sanity check");
236 #endif //ASSERT
237     CompiledICHolder* holder = new CompiledICHolder(call_info->resolved_method()->method_holder(),
238                                                     call_info->resolved_klass(), false);
239     holder->claim();
240     InlineCacheBuffer::create_transition_stub(this, holder, entry);
241   } else {
242     assert(call_info->call_kind() == CallInfo::vtable_call, "either itable or vtable");
243     // Can be different than selected_method->vtable_index(), due to package-private etc.
244     int vtable_index = call_info->vtable_index();
245     assert(call_info->resolved_klass()->verify_vtable_index(vtable_index), "sanity check");
246     entry = VtableStubs::find_vtable_stub(vtable_index);
247     if (entry == NULL) {
248       return false;
249     }
250     InlineCacheBuffer::create_transition_stub(this, NULL, entry);
251   }
252 
253   if (TraceICs) {
254     ResourceMark rm;
255     tty->print_cr ("IC@" INTPTR_FORMAT ": to megamorphic %s entry: " INTPTR_FORMAT,
256                    p2i(instruction_address()), call_info->selected_method()->print_value_string(), p2i(entry));
257   }
258 
259   // We can't check this anymore. With lazy deopt we could have already
260   // cleaned this IC entry before we even return. This is possible if
261   // we ran out of space in the inline cache buffer trying to do the
262   // set_next and we safepointed to free up space. This is a benign
263   // race because the IC entry was complete when we safepointed so
264   // cleaning it immediately is harmless.
265   // assert(is_megamorphic(), "sanity check");
266   return true;
267 }
268 
269 
270 // true if destination is megamorphic stub
is_megamorphic() const271 bool CompiledIC::is_megamorphic() const {
272   assert(CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
273   assert(!is_optimized(), "an optimized call cannot be megamorphic");
274 
275   // Cannot rely on cached_value. It is either an interface or a method.
276   return VtableStubs::entry_point(ic_destination()) != NULL;
277 }
278 
is_call_to_compiled() const279 bool CompiledIC::is_call_to_compiled() const {
280   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
281 
282   // Use unsafe, since an inline cache might point to a zombie method. However, the zombie
283   // method is guaranteed to still exist, since we only remove methods after all inline caches
284   // has been cleaned up
285   CodeBlob* cb = CodeCache::find_blob_unsafe(ic_destination());
286   bool is_monomorphic = (cb != NULL && cb->is_compiled());
287   // Check that the cached_value is a klass for non-optimized monomorphic calls
288   // This assertion is invalid for compiler1: a call that does not look optimized (no static stub) can be used
289   // for calling directly to vep without using the inline cache (i.e., cached_value == NULL).
290   // For JVMCI this occurs because CHA is only used to improve inlining so call sites which could be optimized
291   // virtuals because there are no currently loaded subclasses of a type are left as virtual call sites.
292 #ifdef ASSERT
293   CodeBlob* caller = CodeCache::find_blob_unsafe(instruction_address());
294   bool is_c1_or_jvmci_method = caller->is_compiled_by_c1() || caller->is_compiled_by_jvmci();
295   assert( is_c1_or_jvmci_method ||
296          !is_monomorphic ||
297          is_optimized() ||
298          !caller->is_alive() ||
299          (cached_metadata() != NULL && cached_metadata()->is_klass()), "sanity check");
300 #endif // ASSERT
301   return is_monomorphic;
302 }
303 
304 
is_call_to_interpreted() const305 bool CompiledIC::is_call_to_interpreted() const {
306   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
307   // Call to interpreter if destination is either calling to a stub (if it
308   // is optimized), or calling to an I2C blob
309   bool is_call_to_interpreted = false;
310   if (!is_optimized()) {
311     // must use unsafe because the destination can be a zombie (and we're cleaning)
312     // and the print_compiled_ic code wants to know if site (in the non-zombie)
313     // is to the interpreter.
314     CodeBlob* cb = CodeCache::find_blob_unsafe(ic_destination());
315     is_call_to_interpreted = (cb != NULL && cb->is_adapter_blob());
316     assert(!is_call_to_interpreted || (is_icholder_call() && cached_icholder() != NULL), "sanity check");
317   } else {
318     // Check if we are calling into our own codeblob (i.e., to a stub)
319     address dest = ic_destination();
320 #ifdef ASSERT
321     {
322       _call->verify_resolve_call(dest);
323     }
324 #endif /* ASSERT */
325     is_call_to_interpreted = _call->is_call_to_interpreted(dest);
326   }
327   return is_call_to_interpreted;
328 }
329 
set_to_clean(bool in_use)330 void CompiledIC::set_to_clean(bool in_use) {
331   assert(SafepointSynchronize::is_at_safepoint() || CompiledIC_lock->is_locked() , "MT-unsafe call");
332   if (TraceInlineCacheClearing || TraceICs) {
333     tty->print_cr("IC@" INTPTR_FORMAT ": set to clean", p2i(instruction_address()));
334     print();
335   }
336 
337   address entry = _call->get_resolve_call_stub(is_optimized());
338 
339   // A zombie transition will always be safe, since the metadata has already been set to NULL, so
340   // we only need to patch the destination
341   bool safe_transition = _call->is_safe_for_patching() || !in_use || is_optimized() || SafepointSynchronize::is_at_safepoint();
342 
343   if (safe_transition) {
344     // Kill any leftover stub we might have too
345     clear_ic_stub();
346     if (is_optimized()) {
347       set_ic_destination(entry);
348     } else {
349       set_ic_destination_and_value(entry, (void*)NULL);
350     }
351   } else {
352     // Unsafe transition - create stub.
353     InlineCacheBuffer::create_transition_stub(this, NULL, entry);
354   }
355   // We can't check this anymore. With lazy deopt we could have already
356   // cleaned this IC entry before we even return. This is possible if
357   // we ran out of space in the inline cache buffer trying to do the
358   // set_next and we safepointed to free up space. This is a benign
359   // race because the IC entry was complete when we safepointed so
360   // cleaning it immediately is harmless.
361   // assert(is_clean(), "sanity check");
362 }
363 
is_clean() const364 bool CompiledIC::is_clean() const {
365   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
366   bool is_clean = false;
367   address dest = ic_destination();
368   is_clean = dest == _call->get_resolve_call_stub(is_optimized());
369   assert(!is_clean || is_optimized() || cached_value() == NULL, "sanity check");
370   return is_clean;
371 }
372 
set_to_monomorphic(CompiledICInfo & info)373 void CompiledIC::set_to_monomorphic(CompiledICInfo& info) {
374   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "");
375   // Updating a cache to the wrong entry can cause bugs that are very hard
376   // to track down - if cache entry gets invalid - we just clean it. In
377   // this way it is always the same code path that is responsible for
378   // updating and resolving an inline cache
379   //
380   // The above is no longer true. SharedRuntime::fixup_callers_callsite will change optimized
381   // callsites. In addition ic_miss code will update a site to monomorphic if it determines
382   // that an monomorphic call to the interpreter can now be monomorphic to compiled code.
383   //
384   // In both of these cases the only thing being modifed is the jump/call target and these
385   // transitions are mt_safe
386 
387   Thread *thread = Thread::current();
388   if (info.to_interpreter() || info.to_aot()) {
389     // Call to interpreter
390     if (info.is_optimized() && is_optimized()) {
391        assert(is_clean(), "unsafe IC path");
392        MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
393       // the call analysis (callee structure) specifies that the call is optimized
394       // (either because of CHA or the static target is final)
395       // At code generation time, this call has been emitted as static call
396       // Call via stub
397       assert(info.cached_metadata() != NULL && info.cached_metadata()->is_method(), "sanity check");
398       methodHandle method (thread, (Method*)info.cached_metadata());
399       _call->set_to_interpreted(method, info);
400 
401       if (TraceICs) {
402          ResourceMark rm(thread);
403          tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to %s: %s",
404            p2i(instruction_address()),
405            (info.to_aot() ? "aot" : "interpreter"),
406            method->print_value_string());
407       }
408     } else {
409       // Call via method-klass-holder
410       InlineCacheBuffer::create_transition_stub(this, info.claim_cached_icholder(), info.entry());
411       if (TraceICs) {
412          ResourceMark rm(thread);
413          tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to interpreter via icholder ", p2i(instruction_address()));
414       }
415     }
416   } else {
417     // Call to compiled code
418     bool static_bound = info.is_optimized() || (info.cached_metadata() == NULL);
419 #ifdef ASSERT
420     CodeBlob* cb = CodeCache::find_blob_unsafe(info.entry());
421     assert (cb != NULL && cb->is_compiled(), "must be compiled!");
422 #endif /* ASSERT */
423 
424     // This is MT safe if we come from a clean-cache and go through a
425     // non-verified entry point
426     bool safe = SafepointSynchronize::is_at_safepoint() ||
427                 (!is_in_transition_state() && (info.is_optimized() || static_bound || is_clean()));
428 
429     if (!safe) {
430       InlineCacheBuffer::create_transition_stub(this, info.cached_metadata(), info.entry());
431     } else {
432       if (is_optimized()) {
433         set_ic_destination(info.entry());
434       } else {
435         set_ic_destination_and_value(info.entry(), info.cached_metadata());
436       }
437     }
438 
439     if (TraceICs) {
440       ResourceMark rm(thread);
441       assert(info.cached_metadata() == NULL || info.cached_metadata()->is_klass(), "must be");
442       tty->print_cr ("IC@" INTPTR_FORMAT ": monomorphic to compiled (rcvr klass = %s) %s",
443         p2i(instruction_address()),
444         (info.cached_metadata() != NULL) ? ((Klass*)info.cached_metadata())->print_value_string() : "NULL",
445         (safe) ? "" : " via stub");
446     }
447   }
448   // We can't check this anymore. With lazy deopt we could have already
449   // cleaned this IC entry before we even return. This is possible if
450   // we ran out of space in the inline cache buffer trying to do the
451   // set_next and we safepointed to free up space. This is a benign
452   // race because the IC entry was complete when we safepointed so
453   // cleaning it immediately is harmless.
454   // assert(is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
455 }
456 
457 
458 // is_optimized: Compiler has generated an optimized call (i.e. fixed, no inline cache)
459 // static_bound: The call can be static bound. If it isn't also optimized, the property
460 // wasn't provable at time of compilation. An optimized call will have any necessary
461 // null check, while a static_bound won't. A static_bound (but not optimized) must
462 // therefore use the unverified entry point.
compute_monomorphic_entry(const methodHandle & method,Klass * receiver_klass,bool is_optimized,bool static_bound,bool caller_is_nmethod,CompiledICInfo & info,TRAPS)463 void CompiledIC::compute_monomorphic_entry(const methodHandle& method,
464                                            Klass* receiver_klass,
465                                            bool is_optimized,
466                                            bool static_bound,
467                                            bool caller_is_nmethod,
468                                            CompiledICInfo& info,
469                                            TRAPS) {
470   CompiledMethod* method_code = method->code();
471 
472   address entry = NULL;
473   if (method_code != NULL && method_code->is_in_use()) {
474     assert(method_code->is_compiled(), "must be compiled");
475     // Call to compiled code
476     //
477     // Note: the following problem exists with Compiler1:
478     //   - at compile time we may or may not know if the destination is final
479     //   - if we know that the destination is final (is_optimized), we will emit
480     //     an optimized virtual call (no inline cache), and need a Method* to make
481     //     a call to the interpreter
482     //   - if we don't know if the destination is final, we emit a standard
483     //     virtual call, and use CompiledICHolder to call interpreted code
484     //     (no static call stub has been generated)
485     //   - In the case that we here notice the call is static bound we
486     //     convert the call into what looks to be an optimized virtual call,
487     //     but we must use the unverified entry point (since there will be no
488     //     null check on a call when the target isn't loaded).
489     //     This causes problems when verifying the IC because
490     //     it looks vanilla but is optimized. Code in is_call_to_interpreted
491     //     is aware of this and weakens its asserts.
492     if (is_optimized) {
493       entry      = method_code->verified_entry_point();
494     } else {
495       entry      = method_code->entry_point();
496     }
497   }
498   bool far_c2a = entry != NULL && caller_is_nmethod && method_code->is_far_code();
499   if (entry != NULL && !far_c2a) {
500     // Call to near compiled code (nmethod or aot).
501     info.set_compiled_entry(entry, is_optimized ? NULL : receiver_klass, is_optimized);
502   } else {
503     if (is_optimized) {
504       if (far_c2a) {
505         // Call to aot code from nmethod.
506         info.set_aot_entry(entry, method());
507       } else {
508         // Use stub entry
509         info.set_interpreter_entry(method()->get_c2i_entry(), method());
510       }
511     } else {
512       // Use icholder entry
513       assert(method_code == NULL || method_code->is_compiled(), "must be compiled");
514       CompiledICHolder* holder = new CompiledICHolder(method(), receiver_klass);
515       info.set_icholder_entry(method()->get_c2i_unverified_entry(), holder);
516     }
517   }
518   assert(info.is_optimized() == is_optimized, "must agree");
519 }
520 
521 
is_icholder_entry(address entry)522 bool CompiledIC::is_icholder_entry(address entry) {
523   CodeBlob* cb = CodeCache::find_blob_unsafe(entry);
524   if (cb != NULL && cb->is_adapter_blob()) {
525     return true;
526   }
527   // itable stubs also use CompiledICHolder
528   if (cb != NULL && cb->is_vtable_blob()) {
529     VtableStub* s = VtableStubs::entry_point(entry);
530     return (s != NULL) && s->is_itable_stub();
531   }
532 
533   return false;
534 }
535 
is_icholder_call_site(virtual_call_Relocation * call_site,const CompiledMethod * cm)536 bool CompiledIC::is_icholder_call_site(virtual_call_Relocation* call_site, const CompiledMethod* cm) {
537   // This call site might have become stale so inspect it carefully.
538   address dest = cm->call_wrapper_at(call_site->addr())->destination();
539   return is_icholder_entry(dest);
540 }
541 
542 // ----------------------------------------------------------------------------
543 
set_to_clean(bool in_use)544 void CompiledStaticCall::set_to_clean(bool in_use) {
545   // in_use is unused but needed to match template function in CompiledMethod
546   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
547   // Reset call site
548   MutexLockerEx pl(SafepointSynchronize::is_at_safepoint() ? NULL : Patching_lock, Mutex::_no_safepoint_check_flag);
549 #ifdef ASSERT
550   CodeBlob* cb = CodeCache::find_blob_unsafe(instruction_address());
551   assert(cb != NULL && cb->is_compiled(), "must be compiled");
552 #endif
553 
554   set_destination_mt_safe(resolve_call_stub());
555 
556   // Do not reset stub here:  It is too expensive to call find_stub.
557   // Instead, rely on caller (nmethod::clear_inline_caches) to clear
558   // both the call and its stub.
559 }
560 
is_clean() const561 bool CompiledStaticCall::is_clean() const {
562   return destination() == resolve_call_stub();
563 }
564 
is_call_to_compiled() const565 bool CompiledStaticCall::is_call_to_compiled() const {
566   return CodeCache::contains(destination());
567 }
568 
is_call_to_interpreted() const569 bool CompiledDirectStaticCall::is_call_to_interpreted() const {
570   // It is a call to interpreted, if it calls to a stub. Hence, the destination
571   // must be in the stub part of the nmethod that contains the call
572   CompiledMethod* cm = CodeCache::find_compiled(instruction_address());
573   return cm->stub_contains(destination());
574 }
575 
is_call_to_far() const576 bool CompiledDirectStaticCall::is_call_to_far() const {
577   // It is a call to aot method, if it calls to a stub. Hence, the destination
578   // must be in the stub part of the nmethod that contains the call
579   CodeBlob* desc = CodeCache::find_blob(instruction_address());
580   return desc->as_compiled_method()->stub_contains(destination());
581 }
582 
set_to_compiled(address entry)583 void CompiledStaticCall::set_to_compiled(address entry) {
584   if (TraceICs) {
585     ResourceMark rm;
586     tty->print_cr("%s@" INTPTR_FORMAT ": set_to_compiled " INTPTR_FORMAT,
587         name(),
588         p2i(instruction_address()),
589         p2i(entry));
590   }
591   // Call to compiled code
592   assert(CodeCache::contains(entry), "wrong entry point");
593   set_destination_mt_safe(entry);
594 }
595 
set(const StaticCallInfo & info)596 void CompiledStaticCall::set(const StaticCallInfo& info) {
597   assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
598   MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
599   // Updating a cache to the wrong entry can cause bugs that are very hard
600   // to track down - if cache entry gets invalid - we just clean it. In
601   // this way it is always the same code path that is responsible for
602   // updating and resolving an inline cache
603   assert(is_clean(), "do not update a call entry - use clean");
604 
605   if (info._to_interpreter) {
606     // Call to interpreted code
607     set_to_interpreted(info.callee(), info.entry());
608 #if INCLUDE_AOT
609   } else if (info._to_aot) {
610     // Call to far code
611     set_to_far(info.callee(), info.entry());
612 #endif
613   } else {
614     set_to_compiled(info.entry());
615   }
616 }
617 
618 // Compute settings for a CompiledStaticCall. Since we might have to set
619 // the stub when calling to the interpreter, we need to return arguments.
compute_entry(const methodHandle & m,bool caller_is_nmethod,StaticCallInfo & info)620 void CompiledStaticCall::compute_entry(const methodHandle& m, bool caller_is_nmethod, StaticCallInfo& info) {
621   CompiledMethod* m_code = m->code();
622   info._callee = m;
623   if (m_code != NULL && m_code->is_in_use()) {
624     if (caller_is_nmethod && m_code->is_far_code()) {
625       // Call to far aot code from nmethod.
626       info._to_aot = true;
627     } else {
628       info._to_aot = false;
629     }
630     info._to_interpreter = false;
631     info._entry  = m_code->verified_entry_point();
632   } else {
633     // Callee is interpreted code.  In any case entering the interpreter
634     // puts a converter-frame on the stack to save arguments.
635     assert(!m->is_method_handle_intrinsic(), "Compiled code should never call interpreter MH intrinsics");
636     info._to_interpreter = true;
637     info._entry      = m()->get_c2i_entry();
638   }
639 }
640 
find_stub_for(address instruction,bool is_aot)641 address CompiledDirectStaticCall::find_stub_for(address instruction, bool is_aot) {
642   // Find reloc. information containing this call-site
643   RelocIterator iter((nmethod*)NULL, instruction);
644   while (iter.next()) {
645     if (iter.addr() == instruction) {
646       switch(iter.type()) {
647         case relocInfo::static_call_type:
648           return iter.static_call_reloc()->static_stub(is_aot);
649         // We check here for opt_virtual_call_type, since we reuse the code
650         // from the CompiledIC implementation
651         case relocInfo::opt_virtual_call_type:
652           return iter.opt_virtual_call_reloc()->static_stub(is_aot);
653         case relocInfo::poll_type:
654         case relocInfo::poll_return_type: // A safepoint can't overlap a call.
655         default:
656           ShouldNotReachHere();
657       }
658     }
659   }
660   return NULL;
661 }
662 
find_stub(bool is_aot)663 address CompiledDirectStaticCall::find_stub(bool is_aot) {
664   return CompiledDirectStaticCall::find_stub_for(instruction_address(), is_aot);
665 }
666 
resolve_call_stub() const667 address CompiledDirectStaticCall::resolve_call_stub() const {
668   return SharedRuntime::get_resolve_static_call_stub();
669 }
670 
671 //-----------------------------------------------------------------------------
672 // Non-product mode code
673 #ifndef PRODUCT
674 
verify()675 void CompiledIC::verify() {
676   _call->verify();
677   assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted()
678           || is_optimized() || is_megamorphic(), "sanity check");
679 }
680 
print()681 void CompiledIC::print() {
682   print_compiled_ic();
683   tty->cr();
684 }
685 
print_compiled_ic()686 void CompiledIC::print_compiled_ic() {
687   tty->print("Inline cache at " INTPTR_FORMAT ", calling %s " INTPTR_FORMAT " cached_value " INTPTR_FORMAT,
688              p2i(instruction_address()), is_call_to_interpreted() ? "interpreted " : "", p2i(ic_destination()), p2i(is_optimized() ? NULL : cached_value()));
689 }
690 
print()691 void CompiledDirectStaticCall::print() {
692   tty->print("static call at " INTPTR_FORMAT " -> ", p2i(instruction_address()));
693   if (is_clean()) {
694     tty->print("clean");
695   } else if (is_call_to_compiled()) {
696     tty->print("compiled");
697   } else if (is_call_to_far()) {
698     tty->print("far");
699   } else if (is_call_to_interpreted()) {
700     tty->print("interpreted");
701   }
702   tty->cr();
703 }
704 
705 #endif // !PRODUCT
706